The Boeing 747SP Special Performance N747SP is a join operation between NASA and DLR the German Space agency and the aircraft is named SOFIA as the aircraft is an airborne “Stratospheric Observatory for Infrared Astronomy” platform.

The former Pan Am then United 747SP underwent major modifications in the early 2000s which included the addition of a large opening barn door on the rear port side of the fuselage to allow for a high powered telescope to deployed at altitude for observations of distant galaxies in outer space with minimal interference from the distortions of the earth’s lower atmospheric conditions.